Mr. Liebert P. Nogueira Profile

Liebert P. Nogueira

at Univ of Oslo

SPIE Involvement:

Author

Publications (3)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

SPIE Journal Paper | 22 November 2024 Open Access

Advanced soft tissue visualization in conjunction with bone structures using contrast-enhanced micro-CT

Torben Hildebrand, Qianli Ma, Catherine A. Heyward, Håvard Haugen, Liebert Nogueira

JMI, Vol. 11, Issue 06, 066001, (November 2024) https://doi.org/10.1117/12.10.1117/1.JMI.11.6.066001

Read Abstract +

PurposeMicro-computed tomography (CT) analysis of soft tissues alongside bone remains challenging due to significant differences in X-ray absorption, preventing spatial inspection of bone remodeling including the cellular intricacies of mineralized tissues in developmental biology and pathology. The goal was to develop a protocol for contrast-enhanced micro-CT imaging that effectively visualizes soft tissues and cells in conjunction with bone while minimizing bone attenuation by decalcification.ApproachMurine femur samples were decalcified in ethylenediaminetetraacetic acid and treated with three different contrast agents: (i) iodine in ethanol, (ii) phosphotungstic acid in water, and (iii) Lugol’s iodine. Micro-CT scans were performed in the laboratory setup SkyScan 1172 and at the synchrotron radiation for medical physics beamline in synchrotron radiation facility Elettra. Soft and hard tissue contrast-to-noise ratio (CNR) and contrast efficiency after decalcification were measured.ResultsIn laboratory micro-CT, Lugol’s iodine demonstrated a threefold higher CNR in the bone marrow, representing the soft tissue portion, compared with the bone. Contrast efficiencies, measured in synchrotron micro-CT, were consistent with these findings. Higher resolutions and the specificity of Lugol’s iodine to cellular structures enabled detailed visualization of bone-forming cells in the epiphyseal plate.ConclusionsThe combination of decalcification and the utilization of the contrast agent Lugol’s iodine facilitated an enhanced soft tissue visualization in conjunction with bone.

DOWNLOAD PAPER

Proceedings Article | 17 October 2024 Presentation + Paper

Advanced soft tissue visualization in conjunction with bone structures using contrast-enhanced micro-CT

Torben Hildebrand, Qianli Ma, Catherine Anne Heyward, Håvard Haugen, Liebert Nogueira

Proceedings Volume 13152, 131520J (2024) https://doi.org/10.1117/12.3027063

KEYWORDS: Bone, Tissues, Iodine, Contrast agents, Biological samples, Visualization, Biological imaging, Synchrotrons, Cartilage

Read Abstract +

Micro-CT analysis is conventionally used to investigate mineralized tissues. However, the potential of phase-contrast and contrast-enhanced micro-CT extends to soft tissue inspection, though optimizing soft tissue contrast alongside bone remains challenging, preventing spatial inspection of bone remodeling including the cellular components. The goal was to develop a protocol for contrast-enhanced micro-CT imaging that effectively visualizes soft tissues and cells in conjunction with bone while minimizing bone attenuation by decalcification. Murine femur samples were decalcified in ethylenediaminetetraacetic acid (EDTA) and treated with three different contrast agents: i) iodine in ethanol, ii) phosphotungstic acid (PTA) in water and iii) Lugol’s iodine. Micro-CT scans were performed in the laboratory set-up SkyScan 1172 and at the SYRMEP beamline in ELETTRA. Soft- and hard-tissue contrast-to-noise ratio (CNR) and contrast efficiency after decalcification were measured. In laboratory micro-CT, iodine in ethanol and PTA provided a higher CNR for bone compared to bone marrow, while Lugol’s iodine demonstrated a three-times higher CNR in bone marrow, representing the soft tissue portion. Contrast efficiencies, measured as the percentage increase of gray value compared to its decalcified state prior to contrast enhancement, were consistent with these findings in synchrotron micro-CT. Higher resolutions and the specificity of Lugol’s iodine to cellular structures enabled detailed visualization of bone-forming cells in the epiphyseal plate. The optimized protocol for micro-CT imaging significantly enhances soft tissue visualization alongside bone, facilitating non-invasive anatomical and histological analysis. This approach shows high potential for exploring the cellular intricacies of mineralized tissues in developmental biology and pathology.

Proceedings Article | 4 October 2024 Poster + Paper

Contrast-enhanced micro-CT for visualization of cell distribution in hydrated human cornea

Torben Hildebrand, Gerard Boix-Lemonche, Håvard Haugen, Goran Petrovski, Liebert Nogueira

Proceedings Volume 13152, 1315221 (2024) https://doi.org/10.1117/12.3026984

KEYWORDS: Cornea, Tissues, Iodine, Visualization, Biological samples, Deionized water, Corneal imaging, Biological imaging

Read Abstract +

The human eye’s cornea is vital for visual clarity and quality of life. Besides proteoglycans, an adequate hydration contributes to a transparent cornea by uniform distribution of collagen fibrils. Understanding the cell distribution within the multi-layered cornea is fundamental to investigate corneal physiology and pathology. Micro-CT imaging potentially enables a spatial examination of the cornea. This study employs contrast-enhanced micro-CT to demonstrate the feasibility and expectable precision of X-ray imaging of the intricate multi-layered human cornea. Human donor corneas were hydrated to different degrees, mimicking the in-vivo state of edema formation. Tissue samples were then immersed in Lugol’s iodine for contrast enhancement and scanned by the laboratory micro-CT Skyscan 2211. The effects in the soft tissue contrast were evaluated accordingly. The contrast-to-noise ratios (CNR) for the cell layers, specifically the epithelium and endothelium, were 8.67 ± 1.17 and 5.84 ± 0.53, respectively. In comparison, the stromal tissue exhibited a significantly lower CNR of 1.81 ± 0.29. This discrepancy highlights Lugol's iodine's strong affinity for binding cells, which enhanced the contrast of individual stromal cells relative to the surrounding collagen fibrils, and the potential to be visualized with contrast-enhanced micro-CT. The present study underscores the potential of contrast-enhanced micro-CT for soft tissue applications with multi-laminar ultrastructure. This advanced imaging technique might enhance our understanding of corneal biology and its applications in clinical settings. Additionally, the specific binding properties of Lugol’s iodine demonstrated may extend to other biological samples and thus opens new pathways for virtual/3D histology.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years